Composite materials having a three dimensional fabric that includes threads extending in the X, Y and Z directions are expected to be widely used as structional materials for rockets, aircraft, automobiles, marine vessels and buildings. Such fabrics include a multiplicity of warp strings, and vertical threads and wefts woven perpendicularly in between columns and rows of the warp strings. The fabric is used as a core and impregnated with matrix of a resin or an inorganic substance.
Further, as a method for producing the three dimensional fabric of the type mentioned, various processes are conventionally proposed. (For example, Japanese Patent Publication No. 38673/1979 and Japanese Patent Publication No. 14624/1976). While three dimensional fabrics of the type mentioned are strong enough against tensile loads, compressive loads and bending loads acting in the X, Y and Z directions, they have the drawback that the amount of deformation caused by a force acting in an inclined direction with respect to the axial direction is great.
It is a first object of the present invention to provide a novel three dimensional fabric wherein the amount of deformation by a force acting in an inclined direction is decreased.
It is a second object of the present invention to provide a method for producing a three dimensional fabric readily.